Sex Differences in Muscle-Respiratory Function Relationship in Lung Transplant Patients: A Longitudinal Study

Area of Science:

• Pulmonary Medicine
• Transplantation Surgery
• Musculoskeletal Health

Background:

• Lung transplant recipients face increased risks of sarcopenia and osteoporosis.
• Muscle health's impact on lung function is known, but long-term interplay with pulmonary volumes, especially sex-specific, is understudied.

Purpose of the Study:

• To evaluate the longitudinal relationship between muscle mass and strength and respiratory function in lung transplant patients.
• To conduct sex-specific analyses of muscle parameters and pulmonary function.

Main Methods:

• Prospective cohort study with three assessments (baseline, ~1 year, 2-3 years).
• Primary outcomes: longitudinal changes in pulmonary function (VC, FVC, FEV1, TLC) relative to appendicular skeletal muscle mass index (ASMMI) and handgrip strength (HGS).
• Analyses used multivariable linear regression and linear mixed-effects models, adjusted for relevant covariates.

Main Results:

• At baseline, handgrip strength (HGS) was independently associated with higher vital capacity (VC) and forced expiratory volume in 1 second (FEV1) in both sexes.
• Appendicular skeletal muscle mass index (ASMMI) was independently associated with VC in both men and women.
• Longitudinally, higher HGS correlated with better pulmonary function trajectories; specific associations found between lower ASMMI and higher FEV1/TLC in women with restrictive disease, and stronger HGS with improved TLC in women with cystic fibrosis.

Conclusions:

• Muscle mass and strength are significantly associated with lung function following lung transplantation.
• These findings emphasize the clinical importance of monitoring and managing muscle health in post-transplant care.